To cross a stream, road or valley (the place the delay brought on by a flight of locks at either aspect will be unacceptable) the valley could be spanned by a navigable aqueduct – a famed example in Wales is the Pontcysyllte Aqueduct (now a UNESCO Globe Heritage Site) https://comprar-visualizacao-em-v00998.bloggerchest.com/37137906/the-fact-about-urso-fofo-that-no-one-is-suggesting